Control devices for components such as wireless thermostat controllers or wireless light switches require the use of control circuitry that can operate for long periods of time on a single battery. These types of circuits have long sleep periods wherein minimal power is needed to operate the circuit thus providing a minimal draw on the battery charge. These circuits have very short periods of time when control operations require higher voltage levels in order to accomplish various procedures. In order for these types of circuits to have the necessary operating characteristics, improved circuitries must be provided which will provide optimal power characteristics in both the high power usage and low power usage modes of operation. These types of circuitries also require some type of power control logic enabling ease of switching between these modes of operation having different power usage characteristics.
The power control logic in these types of circuitries require special control during start-up operations. The power control logic cannot begin functioning properly until the system voltage has risen to a desired threshold level. Thus, it is necessary to maintain the power control logic in a reset mode until a desire threshold system voltage can be achieved. However, since the control device is not fully powered up there are some limitations on the types of measurements that can be made across process and temperature variations. Monitoring circuitry for overcoming these issues would be greatly beneficial.